1. Field of the Invention
This invention relates to a machine for use in stripping tobacco leaves from the stalk of a plant after the stalk has been severed from the ground and has hung in a tobacco barn for a predetermined length of time to dry out the leaves.
2. Description of the Prior Art
Tobacco stripping is the most time-consuming step in growing and marketing tobacco. Stripping tobacco consists of pulling each leaf from the stalk by hand. The leaves are graded as they are pulled from the stalk. A grade of leaf means the color or texture of the leaf. Generally, the leaves on the bottom one-third of the stalk are one grade, the leaves in the middle one-third are another grade, and the leaves on the top one-third are a third grade; although the portion of the stalk which contains the three grades may vary. With the recent approval of the use of balers for baling tobacco leaves for shipment and final sale, there has been increased activity in the development of a mechanized stripping method for removing the leaves from the stalk. No patents were found which describe such machines, although there is the Long U.S. Pat. No. 2,949,118, which is described as a tobacco stripping and booking machine. This Long machine is apparently for stripping the stem from the tobacco leaf, rather than for stripping the tobacco leaf from the stalk, as is the present invention. The main purpose of this Long machine is for stacking or booking flexible, pliable sheets or strips of tobacco for subsequent use; for example, as cigar wrappers.
Leaf-stripping machines for use with sugar cane stalks are known in this art, but they are not analogous to the present invention because it is the stalk which is of greatest value in the sugar cane business, while the leaves on the sugar cane stalk are generally discarded. The reverse is true in the tobacco business where the tobacco leaf is of greatest value, and the tobacco stalk is discarded.
The Wynberg U.S. Pat. No. 958,790 describes a machine where the sugar cane is fed lengthwise through a pair of rotating brushes so as to remove the natural wax and other impurities from the cane prior to the cane being crushed and submitted to further treatment.
There are three Pool patents--U.S. Pat. No. 2,723,667, U.S. Pat. No. 2,723,668 and U.S. Pat. No. 2,723,669. All three of these patents relate to a combination stalk chopper and leaf stripper for use with sugar cane where the cane is fed between a pair of corrugated feed rolls, and the leaf foilage is removed by a pair of counter-rotating, leaf-stripping rolls, and then the cane stalk is chopped into short lengths by rotating blades.
The Butcher U.S. Pat. No. 4,292,982 describes a leaf-stripping machine for use with tobacco stalks where one motor drives a rotating stalk support tube having an annular knife edge on the front edge thereof. A belt drive from the said tube drives a pair of counter-rotating elongated rollers to form a nip for pulling the leaves from the stalk as the stalk passes horizontally thereover. Any leaves the rollers fail to pull off will be cut off by the annular knife edge as the stalk is pulled through the rotating tube by a pair of motor-driven in-feed rollers at the rear of the machine. This Butcher machine is basically a one grade stripper machine as distinguished from the present invention which separates the leaves into its various grades in a manner similar to the manual stripping of tobacco leaves.